Introduction

1. With the help of wrapper classes, we can wrap primitives to objects so that we can handle primitives just like objects.

   1. Constructor Summary

      1. Int- Integer(integer,string)

      2. byte- Byte(byte,string)

      3. Char- Character(character)

      4. boolean- Boolean(boolean,string)

      5. Double - Double(double,string)

      6. Float-Float(float,string)

      7. short-Short(short,string)

   2. In all wrapper classes tostring() method overrides to return the content

   3. The equals method is overridden in all wrapper classes to compare the content

## The usage of wrapper classes

1. Utility methods: Helper method/static methods

    1. valueof(): it is used wrapper object for the given primitive or string

        * we can create wrapper classes as

            ```java
            class HelloWorld {
                public static void main(String[] args) {
                   Integer i1 = new Integer(10);
                }
            }
            // this method of creating wrapper classes has been deprecated hence we have one more alternative of creating wrapper classes





            class HelloWorld {
                public static void main(String[] args) {
                   Integer i1= Integer.valueOf(10);// this is the use of value of to create new wrapper classes 
                   System.out.println(i1);
                }
            }

            ```

    2. XXXXvalue()

        * Used to convert objects to primitive

            ```java

            class HelloWorld {
                public static void main(String[] args) {
                   Integer i1= Integer.valueOf(10);
                   System.out.println(i1.intValue());
                   System.out.println(i1.floatValue());
                   System.out.println(i1.byteValue());
                   System.out.println(i1.shortValue());
                   System.out.println(i1.longValue());
                }
            }
            ```

    3. parseXXX()

        * used to convert string to primitive

    4. toString()

        * A `toString()` is an in-built method in Java that returns the value given to it in *string* format. Hence, any object that this method is applied on, will then be returned as a *string object*.


## Autoboxing & Unboxing

1. *Autoboxing* is the automatic conversion that the Java compiler makes between the primitive types and their corresponding object wrapper classes. For example, converting an int to an Integer, a double to a Double, and so on.

2. If the conversion goes the other way, this is called *unboxing*.